<template>
  <div>
    <p>child</p>
    <p>{{ count }}</p>
    <button @click="$emit('update:count', count + 1)">更新</button>
  </div>
</template>

<script>
export default {
  name: "ChildComp",
  props: {
    count: Number,
  },
};
</script>
